1. Field of the Invention
The invention relates to a projector type vehicle lamp including a shading part.
2. Related Art
In general, in a projector type vehicle lamp, light from a light source disposed on a rear side of a rear focal plane of a projection lens is reflected to the projection lens by a reflector.
In such a projector type vehicle lamp, in order to form a light distribution pattern having a cutoff line on an upper end portion thereof, a portion of the reflected light is shielded by a shading part. The shading part is disposed in such a way that an upper edge of the shading part passes through a rear focal point of the projection lens or a vicinity of the rear focal point, for example, as disclosed in Patent Documents 1 to 3.    Patent Document 1: JP-A-2000-156106    Patent Document 2: JP-A-2009-104790    Patent Document 3: JP-A-2010-033740
In the structure of Patent Document 1, the upper edge of the shading part is formed on an inner peripheral edge of an opening of a shade member.
In the structure of Patent Document 2, second right and left reflectors are disposed in front of the upper portion of the shading part.
In general, the light distribution pattern from the projector type vehicle lamp has a tendency in that a forward region at a short range of a road surface in front of the vehicle excessively brightens and both right and left regions thereof get dark.
If the shading part is formed on the upper edge of the opening in the shade member such like the structure of Patent Document 1, it is possible to shield a portion of the reflected light, which passes through a position significantly spaced upward apart from the upper edge of the shading part, at an upper portion of the opening of the shade member. Since the forward region at the short range of the road surface in front of the vehicle does not excessively brighten, it is possible to prevent a relatively less visibility at both right and left regions.
However, even if the this configuration is employed, there is a problem in that brightness of both right and left regions at the short range of the road surface in front of the vehicle cannot be positively increased.
If the pair of second right and left reflectors are disposed upward in front of the shading part such like the structure of Patent Document 2, the reflected light from the second reflectors is added to the reflected light from the reflector, so that the brightness of both right and left regions at the short range of the road surface in front of the vehicle can be increased.
However, even if this configuration is employed, there is a problem in that it is not possible to prevent the forward region at the short range of the road surface in front of the vehicle from excessively brightening due to the reflected light, which passes through the position significantly spaced upward apart from the upper edge of the shading part.
In addition, according to the above configuration, there is another problem in that since the pair of second right and left reflectors are required in addition to the reflector, a cost of the lamp is increased by the increased number of components.